1. *Evidence of Continental Drift

2. *Continental Drift
*Who: Alfred Wegener *What: Thought the continents were once all connect and slowly drifted apart *When: Over millions of years *Why: Continents looked like puzzle pieces; rock & fossil evidence supports this

3. *Evidence of Continental Drift
Wegener gathered evidence from different scientific fields to support his ideas about continental drift. *Wegener studied: land features, fossils, and evidence of climate change.
Landforms

4. *Land Features
*Mountains and other features on the continents line up when you put the “puzzle pieces” together.
Examples
Mountain ranges on Africa and South America line up.
Coal fields from Europe line up with coal fields in North America.

5. Rock/Land Features Evidence

6. *Fossils
Fossil: any trace of an ancient organism that has been preserved in rock
*Fossils from an ancient plant have been found in Africa, South America, Australia, India, and Antarctica.
*This convinced Wegener that Pangaea existed.

7. Other Examples of Fossil Evidence:
*Fresh water reptile fossils are found in places now separated by oceans.
Neither reptile could have swum great distances across salt water.
Must have lived on a single landmass that has since split apart.

8. Fossil Evidence

9. *Climate Towards the equator, climate is warmer.
Towards the poles, climate is colder.
Continents carry fossils and rocks.
*300 million year-old fossils from tropical plants were found on an island in the Arctic Ocean.
*Wegener thought that all the continents were once closer to the equator.

10. More Climate Evidence
Geologists found evidence of cold weather in South Africa.
*Deep scratches in rocks showed that there were once continental glaciers in South Africa.
So...during Pangaea, South Africa must have been much closer to the South Pole and moved over the years.

11. Climate/Glacier Evidence

12. *Wegener’s Hypothesis Rejected
*He could not provide a satisfactory explanation for the force that pushes or pulls the continents.
So his hypothesis was rejected and further studied by geologists for many years.